Welcome to the E46Fanatics forums. E46Fanatics is the premiere website for BMW 3 series owners around the world with interactive forums, a geographical enthusiast directory, photo galleries, and technical information for BMW enthusiasts.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

White spots on the expansion tank means you're leaking coolant at the top once the heat and pressure gets up to the top... Not a head gasket issue, just an issue with leaking at the cap, or somewhere else around that area.

White spots on the expansion tank means you're leaking coolant at the top once the heat and pressure gets up to the top... Not a head gasket issue, just an issue with leaking at the cap, or somewhere else around that area.

yea but the spots on the top arent the things that are worrying me..

im losing 1/4 of a gallong of coolant a day...

most people are saying its my expansion tank...

how do i check if its that and if it is, is it easy to replace and shiet?

Check your expansion tank cap. I got a defective one that didn't seal properly and it caused me to lose coolant out the cap. New cap solved that issue. I also got my car back from the dealership yesterday and they didn't bother to tighten the cap all the way down. I lost 3/8ths a gallon with the cap being loose over a 20 mile drive. It left white coolant residue everywhere including on the expansion tank.

Check your expansion tank cap. I got a defective one that didn't seal properly and it caused me to lose coolant out the cap. New cap solved that issue. I also got my car back from the dealership yesterday and they didn't bother to tighten the cap all the way down. I lost 3/8ths a gallon with the cap being loose over a 20 mile drive. It left white coolant residue everywhere including on the expansion tank.

You can tighten it by hand. It needs to be tight but nothing crazy. The dealership only had the threads started and it was loose. If you're leaking coolant from your cap (whether the cap is defective or loose) there'll be coolant on the threads of the tank.

You can tighten it by hand. It needs to be tight but nothing crazy. The dealership only had the threads started and it was loose. If you're leaking coolant from your cap (whether the cap is defective or loose) there'll be coolant on the threads of the tank.

He is saying to pressurize the cooling system to 1bar(14.5psi). there are tools for this.

__________________

www.E46Turbo330Ci.comWARNING: This modification is known to the State of California to cause cancer and birth defects or other reproductive harm due to the extreme G forces once turbo kicks in. ~ Nivo
The rest of my signature is reserved for pointless modification bits like: Halos | window Tint | carbon fiber roundels | short shifter